Gripping device.



No. 880,090. PATENIED IBB. 25, 1908. o. E. MGMAHON. GRIFFIN@ DEVICE.'

APPLICATION FIVLED APR.23,1907.

1HE NaRms PETERS cc., wAsmNcroN: n. c.

OWEN E. MCMAHON, OF ELGIN, ILLINOIS.

GRIPPING DEVICE.

Specification of Letters Patent.

Patented Feb. 25, 1908.

Application filed April 23| 1907. Serial No. 369.858t

To all whom it may concern:

Be it known that I, OWEN E.MCMAHON, a citizen of the United States, and a resident of Elgin, in the county of Kane and State of Illinois, have invented certain new and useful Improvements in Gripping Devices and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which form a part of this specification.

This invention relates to improvements in gripping devices designed to engage an electric wire cable or the like with a gripping force to draw the same forwardly as, for instance, through an underground conduit, and the invention consist-s in the matters 4hereinafter set forth and more particularly v produce an improved gripping device for this purpose of extremely simple and efficient construction, and one wherein the tractive or pulling force is exerted on the device in a manner to increase the gripping action on the cable.

In the drawings Figure 1 is a side elevatio'n of a gripping device made in accordance with my invention. Fig. 2 is a central longitudinal section thereof. Fig. 3 is a plan view. Fig. 4 is an end view. Fig. 5 is a section taken on line 5-5 of Fig. 2.

As shown in the drawings, A A1 designate two elongated ripping jaws. Said aws are hingedone to t e other at the rear end of the device. The hinge, in the present instance, consists of two laterally separated, rearwardly directed, oblique arms a a, on the lower jaw provided with inwardly extending hinge lugs al and two rearwardly directed, oblique arms a2 a2 on the upper member provided with rearwardly opening notches or sockets adapted to receive said lugs. The said gripping jaws are provided with elongated gripping faces a as which extend to the rear end of the device. The said gripping faces are shown as made transversely concave to receive the round or cylindric cable. The space between the jaws opens rearwardly through the rear end of the device so as to permit a cable to be inserted into said space through said rear opening. The laterally separated hinges are spaced a dist-ance apart to freely receive therebetween a cable and said hinges are located one ateach side of said rear opening.

B designates a tractive or pulling link that is connected with the forward end of the device and is adapted for attachment thereto of a pulling chain or cable. The said link embodies or is combined with features of construction which coperate with the link to serve as a means for locking the jaws pressed upon an interposed cable, and said locking means are so arranged that the grip im* pressed on the cable by the jaws is proportional to the tractive force or pull tending to pull the cable forwardly. For this purpose the said link B comprises a forwardly extending loop to which a drawing or pulling chain or cable is adapted to be attached, one end member b1 of which extends through a slot c of a hook extension CV made integral with a neck a4 which extends forwardly from the lower jaw A1. Extending rearwardly from said link B is a closed locking loop B1, made somewhat larger than the loop t, and the rear end member b1 of said locking loop is adapted, when the link is in its normal or pulling position, to occupy a rearwardly and upwardly inclined notch c1 in said hook extension; said notch giving to this part of the device the general form of a hook as shown in Figs. 1 and 2. The upper jaw A is provided with two forwardly extending arms D D, one on each side of the shank a4. The forward ends d of said arms D are inclined lforwardly and upwardly and lie withtheir inclined upper margins closely adjacent to the rearwardly and upwardly oblique notch c1 of the hook extension O. The upper margins of said inclined portions ofsaid arms intersector extend across the lower margin of said notch c1, as shown in Fig. 1 and are, therefore, in position for engagement by the rear end member b2 of the locking loop.

In the use of the device, the pulling link is shifted rearwardly until the rear end member b2 of the locking loop extension is out of the notch c1, whereupon said link may be swung about the part b1 to the position indicated in dotted lines in Fig. 1, in which position the said locking loop is free from the forwardly extending arms of the upper aw. The said upper jaw may now be swung away from its companion aw sufficiently to permit a cable to be inserted through the rear open end j of the device between the gripping faces of said jaws. Thereafter the jaws are closedupon the cable and said link is rearranged to bring with an inclined vnotch and the other jaw the closed end b2 of the locking loop extension into the notch and into engagement with the upper inclined margins of the locking arms D, as shown in dotted lines in Fig. 1. If now a draft or forward pull be exerted upon said link it will be obvious that the effect of the co-action of said closed end b2 of the locking link with the inclined margins of said locking arms D has the effect, not

only to draw the device and the grippedl cable forwardly, but also to clamp or grip the jaws tightly againstthe cable, and it is further evident that this gripping action is proportional to the pulling force exerted to draw the device and the cable forwardly.

In order to effect an efficient bite of the jaws against an interposed cable, the inner faces of the aws are provided with opposing gripping lugs a5 a5 located out of line with each other. Said gripping lugs are shown as being transversely concave to correspond generally to the contour of the cable gripped thereby. The said lugs, which may be supplemented by others, constitute a roughened surface which engage the interposed cable in a manner to somewhat bend or distort the same out of a straight line and therefore produce a more eflicient gripping action'of the jaws upon the cable.

I claim as my invention l. A gripping device comprising two jaws hinged together at their rear ends, a ulling link having slotted connection with t e forward end of one of the jaws, said latter jaw being provided with an inclined notch an inclined surface on the forward end of the other jaw, and a part on said link engaging said notch and inclined surface and operated by the pulling force on the link to force said jaws together.

2. A gripping device comprising two jaws hinged together at their rear ends, a pulling link provided with a transverse member having slotted connection with the forward end of one of the jaws and provided with a rearwardly extending locking loop, said other jaw being provided with an inclined surface adapted for engagement by said locking loop, as and for the purpose set forth.

3. A gripping device comprising two jaws hinged together at their rear ends, one of said jaws being provided at its forward end with an inclined surface adjacent to said notch, and a pulling link connected with said rst jaw and provided with a locking member loccupying said notch and adapted to engage said inclined surface, as and for the purpose set forth.

4. A gripping device comprising two jaws hinged together at their rear ends, one of said jaws being provided at its forward end with an inclined notch and the other jaw with an inclined surface adjacent to said notch, and a pulling link connected with said first jaw and provided with a locking member occupying said notch and adapted to engage said inclined surface, said link having slotted connection with its associated jaw, permitting the locking member to be disengaged from said notch.

5. A gripping device comprising two jaws j;

hinged together at their rear ends, one of said jaws being rovided with a slotted extension and witfi a rearwardly opening inclined notch and the other jaw being provided with a forwardly inclined arm adja- .fjj

cent to said notch, and a drawing or ulling link having sliding connection wit said slotted extension and provided with arearwardly directed locking loop, a part of which occupies said'inclined notch and is adapted to engage said inclined arm, as and for the purpose set forth.

6. A gripping device comprising two jaws hinged together at their rear ends by laterally separated hinges and constructed to provide between the hinges a rearwardly directed opening to receive a cable to be gripped, a pulling link having slotted connection with the forward end of one of the jaws, said latter jaw having an inclined notch, an inclined surface on the forward end of the other jaw, i

and a part on said link and engaging said notch and inclined surface, for the purpose set forth.

In testimony, that I claim the foregoingas my invention I affix my signature inthe presence of two witnesses, this 23rdday of March A. D. 1907.

OWEN E. MCMAHON.

' Witnesses:

THOMAS MCC'UE, PETER CALLAHAN. 

